// Copyright (c) 2019, The Sispop Project
//
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//
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// permitted provided that the following conditions are met:
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// 1. Redistributions of source code must retain the above copyright notice, this list of
//    conditions and the following disclaimer.
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//    of conditions and the following disclaimer in the documentation and/or other
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#include "random.h"
#include <cassert>

namespace tools {

thread_local std::mt19937_64 rng{std::random_device{}()};

uint64_t uniform_distribution_portable(std::mt19937_64& rng, const uint64_t n)
{
  assert(n > 0);
  const uint64_t secureMax = rng.max() - rng.max() % n;
  uint64_t x;
  do x = rng(); while (x >= secureMax);
  return  x / (secureMax / n);
}

}
